It was the Netherlands that passed the legislation, which then applies to Bonaire.I think just read that BON passed legislation last week that permits them to treat people differently based upon their vaccine status which is intended to let them loosen travel restrictions on those fully vaccinated. I think they were going to waive testing for travel within the ABCs first.
From a speech by the island governor, transcribed at Speech by Island Governor Edison Rijna on May 27th 2021 - Crisiswebsite van het Openbaar Lichaam Bonaire
Last Tuesday the Lower House passed a new bill. This bill makes it possible to draw a policy distinction between people who are fully vaccinated and people who are not fully vaccinated. It means that we are able to differentiate between those groups when they enter Bonaire. We will start making that distinction for travelers entering from Curacao and Aruba. From 1 June onwards, a person coming from Curacao and Aruba may enter Bonaire without a test if they are fully vaccinated. You are fully vaccinated if you have had two coronavirus inoculations and your second inoculation was more than two weeks ago. Currently Aruba and Curacao are investigating whether they will be able to introduce this principle for passengers traveling from Bonaire to those islands as well.